2008 SATURN ASTRA tires

Ination - Tire Pressure
Tires need the correct amount
of air pressure to operate
effectively.
Notice:Do not let anyone tell
you that under-ination or
over-ination is all right. It is
not. If your tires do not have
enough air (under-ination),
you can get the following:
Too much exing
Too much heat
Tire overloading
Premature or irregular wear
Poor handling
Reduced fuel economy
If your tires have too much air
(over-ination), you can get
the following:
Unusual wear
Poor handling
Rough ride
Needless damage from
road hazardsA vehicle specic Tire and
Loading Information label is
attached to your vehicle.
This label shows your vehicle’s
original equipment tires and
the correct ination pressures for
your tires when they are cold.
The recommended cold tire
ination pressure, shown on the
label, is the minimum amount
of air pressure needed to
support your vehicle’s maximum
load carrying capacity.
For additional information
regarding how much weight your
vehicle can carry, and an
example of the Tire and Loading
Information label, seeLoading
the Vehicle on page 8-30.
How you load your vehicle
affects vehicle handling and
ride comfort. Never load
your vehicle with more weight
than it was designed to carry.When to Check
Check your tires once a month
or more. Do not forget to
check the compact spare tire, it
should be at 60 psi (420 kPa).
For additional information
regarding the compact spare
tire, seeCompact Spare Tire on
page 9-67.
How to Check
Use a good quality pocket-type
gage to check tire pressure.
You cannot tell if your tires are
properly inated simply by
looking at them. Radial tires may
look properly inated even
when they are under-inated.
Check the tire’s ination
pressure when the tires are
cold. Cold means your vehicle
has been sitting for at least
three hours or driven no more
than 1 mile (1.6 km).
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Remove the valve cap from the
tire valve stem. Press the
tire gage rmly onto the valve to
get a pressure measurement.
If the cold tire ination pressure
matches the recommended
pressure on the Tire and
Loading Information label, no
further adjustment is necessary.
If the ination pressure is low,
add air until you reach the
recommended amount.
If you overll the tire, release air
by pushing on the metal stem
in the center of the tire valve.
Re-check the tire pressure with
the tire gage.
Be sure to put the valve caps
back on the valve stems.
They help prevent leaks by
keeping out dirt and moisture.High-Speed Operation
{CAUTION
Driving at high speeds, 100 mph
(160 km/h) or higher, puts an
additional strain on tires.
Sustained high-speed driving
causes excessive heat build up
and can cause sudden tire
failure. You could have a crash
and you or others could be
killed. Some high-speed rated
tires require ination pressure
adjustment for high speed
operation. When speed limits
and road conditions are such
that a vehicle can be driven at
high speeds, make sure the
tires are rated for high speed
operation, in excellent
condition, and set to the correct
cold tire ination pressure for
the vehicle load.If the vehicle has P205/55R16 size
tires, additional air pressure is
required when driving the vehicle at
speeds of 99 mph (158 km/h) or
higher. Set the cold tire ination
pressure to the maximum ination
pressure shown on the tire sidewall,
or 32 psi (220 kPa), whichever is
lower. See the example following.
Example:
The maximum load and ination
pressure is molded on the tire’s
sidewall, in small letters, near the
rim ange. It reads something
like this: Maximum load 710 kg
(1565 lbs) 350 kPa (51 psi) Max.
Press.
For this example, the cold tire
ination pressure for high-speed
driving should be set at 32 psi
(220 kPa).
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When high-speed driving ends,
return the tire pressure to the
recommended cold ination
pressure shown on the Tire and
Loading Information label. See
Loading the Vehicle on page 8-30.
Tire pressure should be checked
and correctly set when the tires are
cold. SeeInflation - Tire Pressure
on page 9-46.
Tire Pressure Monitor
System
The Tire Pressure Monitor System
(TPMS) uses radio and sensor
technology to check tire pressure
levels. The TPMS sensors monitor
the air pressure in your vehicle’s tires
and transmit tire pressure readings to
a receiver located in the vehicle.
Each tire, including the spare
(if provided), should be checked
monthly when cold and inated to
the ination pressure recommended
by the vehicle manufacturer on
the vehicle placard or tire inationpressure label. (If your vehicle has
tires of a different size than
the size indicated on the vehicle
placard or tire ination pressure
label, you should determine the
proper tire ination pressure
for those tires.)
As an added safety feature, your
vehicle has been equipped with
a tire pressure monitoring system
(TPMS) that illuminates a low
tire pressure telltale when one or
more of your tires is signicantly
under-inated.
Accordingly, when the low tire
pressure telltale illuminates, you
should stop and check your tires
as soon as possible, and inate them
to the proper pressure. Driving on
a signicantly under-inated tire
causes the tire to overheat and can
lead to tire failure. Under-ination
also reduces fuel efficiency and tire
tread life, and may affect the
vehicle’s handling and stopping
ability.Please note that the TPMS is
not a substitute for proper tire
maintenance, and it is the driver’s
responsibility to maintain correct tire
pressure, even if under-ination has
not reached the level to trigger
illumination of the TPMS low tire
pressure telltale.
Your vehicle has also been equipped
with a TPMS malfunction indicator to
indicate when the system is not
operating properly. The TPMS
malfunction indicator is combined
with the low tire pressure telltale.
When the system detects a
malfunction, the telltale will ash for
approximately one minute and then
remain continuously illuminated.
This sequence will continue upon
subsequent vehicle start-ups as long
as the malfunction exists.
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When the malfunction indicator is
illuminated, the system may not be
able to detect or signal low tire
pressure as intended. TPMS
malfunctions may occur for a variety
of reasons, including the installation
of replacement or alternate tires or
wheels on the vehicle that prevent
the TPMS from functioning properly.
Always check the TPMS malfunction
telltale after replacing one or more
tires or wheels on your vehicle to
ensure that the replacement or
alternate tires and wheels allow
the TPMS to continue to function
properly.
SeeTire Pressure Monitor
Operation on page 9-50for
additional information.Federal Communications
Commission (FCC) and
Industry and Science Canada
The Tire Pressure Monitor System
(TPMS) operates on a radio
frequency and complies with
Part 15 of the FCC Rules.
Operation is subject to the following
two conditions:
1. This device may not cause
harmful interference.
2. This device must accept any
interference received, including
interference that may cause
undesired operation.The TPMS operates on a radio
frequency and complies with
RSS-210 of Industry and Science
Canada. Operation is subject to the
following two conditions:
1. This device may not cause
interference.
2. This device must accept any
interference received, including
interference that may cause
undesired operation of the
device.
Changes or modications to this
system by other than an authorized
service facility could void
authorization to use this equipment.
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Tire Pressure Monitor
Operation
The Tire Pressure Monitor System
(TPMS) is designed to warn the
driver when a low tire pressure
condition exists. TPMS sensors are
mounted onto each tire and
wheel assembly, excluding the
spare tire. The TPMS sensors
monitor the air pressure in the
vehicle’s tires and transmit tire
pressure readings to a receiver
located in the vehicle.
When a low tire pressure condition
is detected, the TPMS illuminates
the low tire pressure warning
light located in the instrument
panel cluster.The low tire pressure warning light
comes on at each ignition cycle
until the tires are inated to
the correct ination pressure.
The low tire pressure warning light
may come on in cool weather
when the vehicle is rst started, and
then turn off as you start to drive.
This could be an early indicator that
the air pressure in the tire(s) are
getting low and need to be inated
to the proper pressure.
You must begin driving before the
TPMS system is operational.
TPMS sensors need to be installed
onto the full-size tire and wheel
assemblies, and the tires adjusted
to the manufacturers’ recommended
tire pressure amount.
A Tire and Load Information label is
attached to the vehicle, and shows
the size of the vehicle’s original
equipment tires and the correct
ination pressure for the tires when
they are cold. SeeLoading the
Vehicle on page 8-30, for anexample of the Tire and Load
Information label and its location on
the vehicle. Also seeInflation - Tire
Pressure on page 9-46.
The vehicle’s TPMS can warn you
about a low tire pressure condition
but it does not replace normal tire
maintenance. SeeTire Inspection
and Rotation on page 9-51andTires
on page 9-38.
Notice:Liquid tire sealants
could damage the Tire Pressure
Monitor System (TPMS) sensors.
Sensor damage caused by
using a tire sealant is not covered
by your warranty. Do not use
liquid tire sealants.
Each TPMS sensor has a unique
identication code. Any time
you replace one or more of the
TPMS sensors or rotate the
vehicle’s tires, the identication
codes are automatically learned by
the TPMS. This occurs within a
few moments of driving the vehicle
over 19 mph (31 km/h).
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TPMS Malfunction Light
The TPMS will not function properly
if one or more of the TPMS
sensors are missing or inoperable.
When the system detects a
malfunction, the low tire warning
light ashes for about one minute
and then stays on for the remainder
of the ignition cycle. Some of the
conditions that can cause the
malfunction light to come on are:
One of the road tires has been
replaced with the spare tire. The
spare tire does not have a TPMS
sensor. The TPMS malfunction
light and DIC message should go
off once you re-install the road tire
containing the TPMS sensor.
One or more TPMS sensors are
missing or damaged. The TPMS
malfunction light should go off
after the TPMS sensors are
installed and the vehicle is
driven for a few moments over
19 mph (31 km/h). See your
dealer/retailer for service.
Replacement tires or wheels do
not match the vehicle’s original
equipment tires or wheels. Tires
and wheels other than those
recommended for the vehicle
could prevent the TPMS from
functioning properly. SeeBuying
New Tires on page 9-54.
Operating electronic devices or
being near facilities using radio
wave frequencies similar to the
TPMS could cause the TPMS
sensors to malfunction.
If the TPMS is not functioning it
cannot detect or signal a low tire
condition. See your dealer/retailer
for service if the TPMS malfunction
light comes on and stays on.
Tire Inspection and
Rotation
Inspect tires regularly for signs of
wear or damage. Also inspect the
spare tire. For more information
on tire inspection, seeWhen It Is
Time for New Tires on page 9-53.
Rotating vehicle tires helps them
to wear evenly and keeps the
vehicle performing like it did
when tires were new.
Rotate the tires and check
wheel alignment approximately
every 5,000 to 8,000 miles
(8 000 to 13 000 km) or when
unusual tire wear is noted.
See “Scheduled Maintenance”
in the Index of the “Limited
Warranty, Maintenance
and Owner Assistance
Information” manual for more
information. Also check the
wheels for damage, seeWheel
Replacement on page 9-58
for more information.
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Use this pattern when rotating
the vehicle tires. Do not include
the compact spare tire in the
tire rotation.
{CAUTION
Rust or dirt on a wheel, or
on the parts to which it is
fastened, can make wheel
bolts become loose after
time. The wheel could come
off and cause a crash. When
you change a wheel, remove
any rust or dirt from places
where the wheel attaches to
the vehicle using a scraper
or wire brush.
Installing wheels with a good
metal-to-metal contact at
the mounting surfaces is
necessary to prevent wheel
bolts from becoming loose.To prevent corrosion or rust
build-up, lightly coat the wheel
hub center and the cone-shaped
surface of each wheel bolt
with wheel bearing grease,
after a wheel change.
SeeChanging a Flat Tire on
page 9-60for information
on installing the tire and wheel
assembly. Also see “Wheel
Bolt Torque” underCapacities
and Specifications on page 10-2.
Adjust the front and rear tires to
the recommended cold tire
ination pressure shown on the
Tire and Loading Information
label. SeeInflation - Tire
Pressure on page 9-46and
Loading the Vehicle on
page 8-30.
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When It Is Time for
New Tires
Various factors, such as
maintenance, temperatures,
driving speeds, vehicle loading,
and road conditions inuence
when you need new tires.
One way to tell when it is time for
new tires is to check the treadwear
indicators, which will appear when
the tires have only 1/16 inch
(1.6 mm) or less of tread remaining.You need new tires if any of the
following statements are true:You can see the indicators at
three or more places around
the tire.
You can see cord or fabric
showing through the tire’s rubber.
The tread or sidewall is cracked,
cut, or snagged deep enough to
show cord or fabric.
The tire has a bump, bulge,
or split.
The tire has a puncture, cut, or
other damage that cannot be
repaired well because of the size
or location of the damage.The rubber in tires degrades over
time, even if they are not being
used. This is also true for the
spare tire, if the vehicle has one.
Multiple conditions affect how
fast this aging takes place, including
temperatures, loading conditions,
and ination pressure maintenance.
With proper care and maintenance
tires typically wear out before
they degrade due to age. If you are
unsure about the need to replace
the tires as they get older, consult
the tire manufacturer for more
information.
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